The Datepicker field needs a look at. I’m getting $.browser errors.
.browser was finally removed since being deprecated in 1.3.
It appears the datepicker jQ UI file that is being included with ACF is the culprit.
I may need to update the datepicker JS.
I went ahead and copy/pasted the latest datepicker build from jQuery UI and it works now. Your specific input JS seems to be fine.